Image sensor and imaging device

Abstract

An image sensor includes a semiconductor substrate including a plurality of pixel regions, a first surface, and a second surface opposing the first surface, a plurality of transistors adjacent to the first surface of the semiconductor substrate in each of the plurality of pixel regions, a microlens on the second surface of the semiconductor substrate, and a plurality of conductive patterns in contact with the semiconductor substrate and closer to the second surface of the semiconductor substrate than to the first surface of the semiconductor substrate in each of the plurality of pixel regions.

What is claimed is: 
     
       1. An image sensor comprising:
 a semiconductor substrate including a plurality of pixel regions, a first surface, and a second surface opposing the first surface; 
 a plurality of transistors adjacent to the first surface of the semiconductor substrate in each of the plurality of pixel regions; 
 a microlens on the second surface of the semiconductor substrate; and 
 a plurality of conductive patterns directly in contact with the second surface of the semiconductor substrate to form a Schottky barrier between the plurality of conductive patterns and the second surface of the semiconductor substrate, the plurality of conductive patterns being closer to the second surface of the semiconductor substrate than to the first surface of the semiconductor substrate in each of the plurality of pixel regions, and the plurality of conductive patterns being configured to conduct electrons generated by an optical signal to the semiconductor substrate over the Schottky barrier. 
 
     
     
       2. The image sensor of  claim 1 , wherein the plurality of conductive patterns have at least one of a line shape or a lattice shape. 
     
     
       3. The image sensor of  claim 1 , wherein
 the plurality of pixel regions includes a first pixel region and a second pixel region adjacent to each other; and 
 the plurality of conductive patterns includes a first conductive pattern and a second conductive pattern, the first conductive pattern contacts the second surface of the semiconductor substrate in the first pixel region, the second conductive pattern contacts the second surface of the semiconductor substrate in the second pixel region, and the first conductive pattern has a first shape different from a second shape of the second conductive pattern. 
 
     
     
       4. The image sensor of  claim 3 , wherein the first conductive pattern includes a first plurality of lines extending in a first direction, and the second conductive pattern includes a second plurality of lines extending in a second direction different from the first direction. 
     
     
       5. The image sensor of  claim 1 , wherein the plurality of conductive patterns are electrically connected to each other throughout the plurality of pixel regions. 
     
     
       6. The image sensor of  claim 1 , wherein a bottom surface of the plurality of conductive patterns is directly on the second surface of the semiconductor substrate. 
     
     
       7. The image sensor of  claim 1 , wherein the plurality of conductive patterns are in the semiconductor substrate, and each of the plurality of conductive patterns has a top surface coplanar with the second surface of the semiconductor substrate. 
     
     
       8. The image sensor of  claim 7 , further comprising:
 a pixel isolation layer forming a boundary between the plurality of pixel regions, at least some of the plurality of conductive patterns being on the pixel isolation layer. 
 
     
     
       9. The image sensor of  claim 7 , wherein the plurality of conductive patterns are along an internal surface of a trench formed by the semiconductor substrate, the trench extends from the second surface of the semiconductor substrate, and an insulating pattern is in a plurality of internal spaces formed by the plurality of conductive patterns. 
     
     
       10. The image sensor of  claim 1 , wherein the semiconductor substrate includes an impurity region adjacent to the plurality of conductive patterns and doped with impurities of a first conductivity type. 
     
     
       11. The image sensor of  claim 1 , wherein the conductive patterns may include at least one of a metal material, a metal silicide material, or a transparent conductive material. 
     
     
       12. The image sensor of  claim 1 , further comprising:
 an optical insulating layer between the microlens and the semiconductor substrate, the optical insulating layer covering the plurality of conductive patterns. 
 
     
     
       13. The image sensor of  claim 1 , wherein each of the plurality of conductive patterns includes a first conductive layer and a second conductive layer, the first conductive layer includes a first conductive material different from a second conductive material of the second conductive layer, and the second conductive layer is closer to the microlens than to the first conductive layer. 
     
     
       14. The image sensor of  claim 13 , wherein each of the plurality of conductive patterns includes a pattern insulating layer between the first conductive layer and the second conductive layer.